The overall objective of this research is to evaluate the trauma program in Illinois. In order to accomplish this, a study involving three major components has been designed. The first component is a sample survey of hospitals not in the system of Trauma Centers. From these hospitals, records of cases of tracer conditions representing a spectrum of trauma severity from mild to severe will be sampled. The resulting data will be used in combination with records of cases of the same tracer conditions treated in Trauma Centers and stored in a computerized Registry for purposes of estimating the proportion of cases treated at Trauma Centers. In addition, the survey will investigate the influence on this proportion of such factors as circumstances of the accident, nature and severity of the injury, distance from accident site to nearest hospitals, and demographic characteristics of the injured patients. The second component is a validation study of the Registry. Finally, a case-control follow-up study of a sample of cases from Trauma Centers and non-Trauma Centers will be conducted for purposes of comparing the two with respect to such patient outcome measures as length of hospitalization, resulting disability and to measures relating to patient satisfaction and cost of the episode.